| 摘要 |
<p>The gel range of acid-acting delayed-action gelling agents, such as sodium silicofluoride, in latex spread foam compounds which are to be gelled by subjecting them to a preliminary heat treatment prior to drying is substantially broadened by including a water-soluble ammonium or amine sulfamate in the compound. At least 0.5 parts by weight of the sulfamate should be used per 100 parts by weight of dry solids in the starting uncompounded latex. It can be added to the latex at any time before or during the compounding step and it is preferably added with 0.5-1 part of a soap per part of sulfamate and also with sufficient ammonium hydroxide or other ammonia donor compound to maintain the pH of the compounded latex composition at 9.5 or higher.</p> |
